ThereWasOnceAGirl Ask your GP for a dietician referral. I did and have lost 2 stone (from your current weight down to 11st7lb).
I'm now aiming to get to down to a healthy BMI of 23 - 24 and stay there.
(I put on over a stone very fast due to psychiatric medications (I changed meds luckily). I looked at all my meds and asked to change to versions that don't make me pile on weight.)
How i'm doing it (with dietician guidance):
1500 cals a day - you have to be really strict. All food items to contain less than 3g saturated fat per 100g. And a only a very low amount of sugar per 100g.
3 meals a day with 2 - 3 snacks. Each meal should contain starchy carbs (for energy), low fat protein and plenty of veg / fruit.
I've cut out all calorific drinks - no fruit juices, alcohol, full sugar sodas - drink lots of water, or diet drinks, or tea / coffee with skimmed milk only.
Also cut out are cakes, chocolate, sweets, crisps, takeaways, deep fried food inc. chips, oil, butter, extra sugar inc. honey, cream, ice cream, and fatty cuts of meat inc. sausage & burgers; pizza, full fat cheese.
I allow myself 2 small treats a week eg 1 scoop of ice cream with my coffee in Thorntons café; 1 small glass of wine at the pub one evening.
It sounds difficult and it is. But you get to love the taste of healthy food.
Learning about food labels and ingredients really helps.
Exercise helps too - I go to the gym for 50 minutes at least 3 times a week and walk everywhere. Lifting weights is good because your body continues to burn fat for 24 hrs after.
Learn what your body fat and visceral body fat % are. THis is very motivating.
If I can do it (I had the worst sweet tooth) then so can you.